Ok, my Extender is at FW 1.01, so I guess I need to go through a rigorous testing process....upgrade Extender & see if stable with Router 1.11, then upgrade Router to 1.20. At least, I can now down-grade the router successfully if it doesn't work!!

I'll work on this over the next few days and let you know the results.

The 1.20 firmware on the 890L did fix Wi-Fi security issues so maybe it is buggy with the extender. I can request a test with the techs.

GreenBay42, I really would appreciate you requesting further testing on this. I really don't want to run my DIR-890L Router on insecure firmware. When I reported this issue over 6 months ago, it was very reproducible!!

FYI, the older version of FW is not insecure, unless you run the 890L in AP mode. Its safe in router mode. I'm sure D-Link is working on testing and will get something planned for a fix as soon as possible. Please be patient.

I ran the 1860 (firmware 1.04) for 9 hours last night connected to my 890L (1.20 firmware) and did not receive any drops. I connected a camera and my phone (android) to the extender over night. It is currently at home with 2 mydlink cameras connected (they always send traffic to the mydlink servers so I will get notified if they drop during the day).